Crush a few pieces into a fine powder. Then put it into a pan with some water and a little jet dry or just dish soap. Pan the material very, very cafefully. Hardrock gold can be tiny. If you get some colors, then the ore is free-milling and probably good grade. If there is only a small amount of ore available, then there is no sense in investing in crushers. If the ore is hard, you might have someone slice a piece in half. Gold will show nicely (will glare brightly in the sun) when ore is cut with a diamond blade. Have fun.